1. Field of the Invention
The present invention relates to a hydraulic system with a multi-flow hydraulic pressure supply unit, especially a dual-flow hydraulic pressure supply unit, such as a pump, through which a volumetric flow of hydraulic fluid is fed to a hydraulic-fluid-operated device. The invention also relates to an automatic transmission for motor vehicles.
2. Description of the Related Art
In modern motor vehicles, hydraulic systems in which at least one pressure supply unit supplies at least one hydraulic-fluid-operated device with a defined pressure are being used to improve safety and comfort. The known hydraulic systems indeed have a high power density, a low power-weight ratio, and high dynamics, but they nonetheless require more energy in relation to regulated electric drives, which leads to higher fuel consumption. Previously, mostly single-flow pumps have been used to supply pressure to, for example, automatic transmissions. Single-flow here means that the pump conveys one pump flow. In contrast, multi-flow pumps convey several pump flows independently of one another. The pump flows are thus connected in parallel.
An object of the present invention is to reduce the losses in known hydraulic systems. The hydraulic pressure supply unit used in the hydraulic system should meet the demands of the automotive industry over a wide range of hydraulic requirements.